Missouri River High BridgeBNSF Missouri River Railroad CrossingBismarck, ND

• Structure ID:

N/A

• Location:

River Mile 1315.0

• River Elevation:

1,625 Feet

• Railroad:

BNSF, Former Northern Pacific

• Daily Traffic Count:

20 Trains Per Day (Estimated)

• Bridge Type:

Steel Through Truss, 3 Truss Spans

• Length:

1,525 Feet, 404 Foot Longest Span

• Width:

1 Track

• Navigation Channel Width:

Non-Navigable

• Height Above Water:

70 Feet

• Date Built:

Opened October 21, 1882

The Northern Pacific Railroad was pushing west in the late 1860s and early
1870s. They reached Bismarck, North Dakota, in 1873. But that was the
end of the line for almost ten years as the NP developed a strategy for
moving west, and raised money for expansion. That expansion would include
conquering the biggest obstacle between their home base in Brainerd,
Minnesota, and the Pacific Ocean, which was the Mighty Mo River.

The NP announced in 1879 that they were building west another 200 miles
to the Yellowstone River, near the Montana state line. According to the
Mandan Historical Society, thousands of people moved into the Bismarck
area looking for work. Many settled in a work camp just west of the
Missouri River, which the the present day location of the City of Mandan.

Work began on the bridge September 1, 1881. The east truss span was
finished May 9, 1882, the west span on June 3, 1882, and the center span
was finished October 18, 1882. The bridge cost just over $1-million to
build, which was big money in the late 1800s. The bridge features four
large granite piers. The stone work on these piers give the bridge a
very elegant yet sturdy look.

Early bridge photos show that the truss sections were flat on top, and
they included both cables and braces in the structure. Current day photos
show the truss sections to be humpback shapes that do not use cables as
structural members. The truss spans were replaced in 1905 to support
heavier locomotives. The rebuilt bridge was located on the 1882 piers.

The huge debt from the High Bridge and westward expansion caused real
problems for the NP. It survived until a panic in 1893 pushed the
railroad into bankruptcy. From there, the line was bought and sold
to a number of railroad tycoons, until it again went public in the
20th century. The NP name came to an end on March 2, 1970, when it
merged with the Great Northern and the Chicago, Burlington, and Quincy
to become the Burlington Northern. The BN later merged with the Santa
Fe Railway to become the BNSF, the current owners of the High Bridge.
Rail traffic dropped on the high bridge after the 1970 merger when the
BN used the former GN mainline in favor of the NP mainline. Traffic
on the NP mainline and the High Bridge have dramatically increased
in recent years due to long unit trains hauling coal out of the Powder
River Basin in Wyoming.

Based on a paper written by Ed Murphy of the ND Geological Survey, the
railroad (first Northern Pacific, and now BNSF), have had endless problems
with the eastern pier of the High Bridge. Just after completion, the east
pier began shifting towards the Missouri River at a rate of 3 to 3-1/2
inches per year. A number of repairs were attempted, but none seemed to
work. In 1898, the pier was dug out and moved back onto a larger foundation.
By 1902, the pier was already 4 inches off center. After further
investigation, it was suspected that the city water reservoir located on
a hill above the railroad track was leaking large amounts of water, causing
the entire hillside to slide towards the river. The NP built a tunnel
under the area to try to drain the water, but the pier continued to move.
More projects were completed in 1918, 1923, and 1940 to try to slow down
the landslide. In 1951, the NP undertook a major project to cut down
the hill and regrade the area. This helped the situation by slowing down
the movement to 1/3 of an inch per year, but did not stop the movement.